Genomic changes and biochemical alterations of seed protein and oil content in a subset of fast neutron induced soybean mutants

Authors: ISLAM, NAZRUL - Oak Ridge Institute For Science And Education (ORISE); STUPAR, ROBERT - University Of Minnesota; Luthria, Devanand - Dave; Garrett, Wesley; STEC, ADRIAN - University Of Minnesota; ROESSLER, JEFF - University Of Minnesota; Natarajan, Savithiry - Savi

Submitted to: BMC Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2019
Publication Date: 10/12/2019
Citation: Islam, N., Stupar, R., Luthria, D.L., Garrett, W.M., Stec, A.O., Roessler, J., Natarajan, S.S. 2019. Genomic changes and biochemical alterations of seed protein and oil content in a subset of fast neutron induced soybean mutants. Biomed Central (BMC) Plant Biology. 19(1):420. https://doi.org/10.1186/s12870-019-1981-x.
DOI: https://doi.org/10.1186/s12870-019-1981-x

Interpretive Summary: Soybean is an important source of food and animal feed due to its high protein, oil, and carbohydrate content. Soybean has been genetically manipulated through natural breeding and natural mutation, and transgenic approaches have been used to engineer soybeans to produce value-added nutritional traits. Another way of altering soybean traits, fast neutrons (FN) irradiation is intriguing because it yields a variety of mutations not easily found in nature. In this report, scientists at USDA-ARS, Beltsville, MD, and scientists at the Univeristy of Minnesota have evaluated soybeans mutagenized by FN irradiation. The scientists investigated protein and oil composition in ten FN mutants and identified one with high protein and low oil content. A special technique called Comparative Genomic Hybridization was used to identify the genes that were mutated. The protein and oil profiles of the 10 mutants were correlated with the gene mutations. The results reveal sets of genes that regulate seed composition and protein content traits. These data are expected to assist scientists and breeders working in government laboratories, universities, and private companies who are interested in understanding protein and oil traits in soybeans or who are interested in developing soybeans with improved traits.

Technical Abstract: Soybean has been subjected for genetic manipulation by breeding, mutation, and transgenic approaches to produce value-added quality traits. Among those genetic approaches, mutagenesis through fast neutrons (FN) radiation is intriguing because it yields a variety of mutations, including single/multiple gene deletions and/or duplications. From a large population of fast neutrons mutagenic plants, we selected ten mutants based on total oil and protein content. These samples were further analyzed for proteins and fatty acid methyl esters profiles along with amino acid and starch content. The mutant 2R29C14Cladecr233cMN15 (nicknamed in this study as L10) showed the highest protein and lower oil content compared to wild type, followed by three other lines (nicknamed in this study as L03, L05, and L06). We physically mapped the position of the gene deletions or duplications in each mutant using comparative genomic hybridization. In addition, we characterized the fatty acid methyl esters profile of the trans-esterified oil and found the presence of five major fatty acids (palmitic, stearic, oleic, linoleic, and linolenic acids) at varying proportions among the mutants. Protein profile using SDS-PAGE of the ten mutants did exhibit a discernable variation between storage (glycinin and ß-conglycinin) and anti-nutritional factor (trypsin inhibitor) proteins. Characterization of protein and oil profiles in soybean FN mutants will be useful for scientist and breeders to alter genes to produce new value-added soybeans.